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Numerical prediction of a flashing flow of saturated water at high pressure

  • Jo, Jong Chull (Korea Institute of Nuclear Safety, Reactor System Evaluation Dept.) ;
  • Jeong, Jae Jun (Pusan National University, School of Mechanical Engineering) ;
  • Yun, Byong Jo (Pusan National University, School of Mechanical Engineering) ;
  • Moody, Frederick J. (Consultant)
  • Received : 2018.02.20
  • Accepted : 2018.06.03
  • Published : 2018.10.25

Abstract

Transient fluid velocity and pressure fields in a pressurized water reactor (PWR) steam generator (SG) secondary side during the blowdown period of a feedwater line break (FWLB) accident were numerically simulated employing the saturated water flashing model. This model is based on the assumption that compressed water in the SG is saturated at the beginning and decompresses into the two-phase region where saturated vapor forms, creating a mixture of steam bubbles in water by bulk boiling. The numerical calculations were performed for two cases of which the outflow boundary conditions are different from each other; one is specified as the direct blowdown discharge to the atmosphere and the other is specified as the blowdown discharge to an extended calculation domain with atmospheric pressure on its boundary. The present simulation results obtained using the two different outflow boundary conditions were discussed through a comparison with the predictions using a simple non-flashing model neglecting the effects of phase change. In addition, the applicability of each of the non-flashing water discharge and saturated water flashing models for the confirmatory assessments of new SG designs was examined.

Keywords

References

  1. S. Gallardo, A. Querol, G. Verdu, Simulation of a main steam line break with steam generator tube rupture using trace, in: Proceedings of the PHYSOR, American Nuclear Society, Knoxville, TN, USA, 2012, pp. 2131-2144.
  2. L. Wolf, Experimental results of coupled fluid-structure interactions during blowdown of the HDR-vessel and comparisons with pre- and post-test predictions, Nucl. Eng. Des. 70 (1982) 269-308. https://doi.org/10.1016/0029-5493(82)90150-9
  3. P. Saha, A. Ghosh, T.K. Das, S. Ray, Numerical simulation of pressure wave time history inside a steam generator in the event of main steam line break and feedwater line break transients, in: Proceedings of the Transient Phenomena in Nuclear Reactor Systems, ASME HTD-vol. 245/NE, vol. 11, 1993, pp. 131-140.
  4. H. Tinoco, Three-dimensional modeling of a steam-line break in a boiling water reactor, Nucl. Sci. Eng. 140 (2002) 152-164. https://doi.org/10.13182/NSE02-A2251
  5. K.H. Kang, H.S. Park, S. Cho, N.H. Choi, S.W. Bae, S.W. Lee, Y.S. Kim, K.Y. Choi, W.P. Baek, M.Y. Kim, Experimental study on the blowdown load during the steam generator feedwater line break accident in the evolutionary pressurized water reactor, Ann. Nucl. Ener 38 (2011) 953-963. https://doi.org/10.1016/j.anucene.2011.01.022
  6. O. Hamouda, D.S. Weaver, J. Riznic, Loading of Steam Generator Tubes during Main Steam Line Breaks, CNSC Contract No. 87055-11-0417- R430.3, RSP-0305, Canadian Nuclear Safety Commission, 2015.
  7. J.C. Jo, F.J. Moody, Transient thermal-hydraulic responses of the nuclear steam generator secondary side to a main steam line break, ASME JPVT 137 (2015), 041301-1-7.
  8. J.C. Jo, B.K. Min, J.J. Jeong, Evaluation of a numerical analysis model for the transient response of nuclear steam generator secondary side to a sudden steam line break, ASME JPVT 139 (2017), 041301-1-7.
  9. O. Hamouda, D.S. Weaver, J. Riznic, An experimental model study of steam generator tube loading during a sudden depressurization, ASME JPVT 138 (2016), 041302-1-11.
  10. J.C. Jo, F.J. Moody, Effects of a venturi type flow restrictor on the thermalhydraulic response of the secondary side of a pressurized water reactor steam generator to a main steam line break, ASME JPVT 138 (2016), 041304-1-12.
  11. J.C. Jo, J.J. Jeong, F.J. Moody, Transient hydraulic response of a pressurized water reactor steam generator to a feedwater line break using the nonflashing liquid flow model, ASME JPVT 139 (2017), 031302-1-8.
  12. KHNP, APR+ Standard Safety Analysis Report, KHNP, Seoul, 2011.
  13. J. Weisman, A. Tentner, Models for estimation of critical flow in two-phase systems, Prog. Nucl. Ener 2 (1978) 183-197. https://doi.org/10.1016/0149-1970(78)90007-0
  14. J.R. Simones-Moreira, M.M. Vieira, E. Angelo, Highly expanded flashing liquid jets, J. Thermophysics Heat Transfer 16 (2002) 415-424. https://doi.org/10.2514/2.6695
  15. R.E. Henry, H.K. Fauske, The two-phase critical flow of one-component mixtures in nozzles, orifices, and short tubes, ASME J. Heat Transfer 93 (1971) 179-187. https://doi.org/10.1115/1.3449782
  16. K.H. Ardron, R.A. Furness, A study of the critical flow models used in reactor blowdown analysis, Nucl. Eng. Des. 39 (1976) 257-266. https://doi.org/10.1016/0029-5493(76)90074-1
  17. D. Bestion, F. D'Auria, P. Lien, H. Nakamura, A State-of-the-art Report on Scaling in System Thermal Hydraulics Applications to Nuclear Reactor Safety and Design, OECD Nuclear Energy Agency, Paris, France, 2017. NEA/CSNI/R(2016)14.
  18. ANSYS CFX User's Guide-14, ANSYS Inc., NY, 2012.
  19. F.R. Menter, Two equation eddy-viscosity turbulence models for engineering applications, AIAA J. 32 (1994) 1598-1604. https://doi.org/10.2514/3.12149
  20. C.M. Rhie, W.L. Chow, Numerical study of the turbulent flow past an airfoil with trailing edge separation, AIAA J. 21 (1983) 1525-1532. https://doi.org/10.2514/3.8284
  21. S. Majumdar, Role of under-relaxation in momentum interpolation for calculation of flow with non-staggered grids, Num. Heat Transfer 13 (1988) 125-132.
  22. F.R. Zaloudek, The Critical Flow of Hot Water through Short Tubes, 1963. HW-77594, General Electric, WA, USA.
  23. L.S. Tong, J. Weisman, Thermal Analysis of Pressurized Water Reactors, ANS, La Grange Park, Il., USA, 1979.

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